Infa-Red Control
Slugg
Posts: 4
So I'm sure this has been asked before, but I can't seem to find it. I am interested in building a home control system. I used to install package control systems (under a variety of brand names) as a summer job years ago. I always thought it would be possible to build your own cheaper than the manufacturers were charging (plus the install/programming).
Has anyone successfully controlled an entertainment system with the basic stamp via infared? I have found a ton of documentation on how to control the stamp with a remote, but what about vice-versa?
The parts that intimidates me the most are:
1) Finding the codes the equipment needs per command.
-Now I figured that if I could build a circuit to read the remote for that piece of equipment I could then find the code for each button.... but then I hit problem number 2
2) How do i know what frequency they are utilizing.
-
I didn't realize until now I could probably google the equipment and find the frequency and codes.
Anyhow, I would still benefit from any thoughts you all may have on a DIY home control system. My ultimate goal is to create a home control that will display all the menus/etc... as video. Then use a keyboard/mouse to interface. The system will control the T/V, DVD, VCR (I'm not old...I'm vintage), stereo, lights, shades and monitor outside temp (plus some other bells and whistles I'm sure). My only real confusion is the IR.
I always enjoy reading all your posts. Thanks
Phill
Has anyone successfully controlled an entertainment system with the basic stamp via infared? I have found a ton of documentation on how to control the stamp with a remote, but what about vice-versa?
The parts that intimidates me the most are:
1) Finding the codes the equipment needs per command.
-Now I figured that if I could build a circuit to read the remote for that piece of equipment I could then find the code for each button.... but then I hit problem number 2
2) How do i know what frequency they are utilizing.
-
I didn't realize until now I could probably google the equipment and find the frequency and codes.
Anyhow, I would still benefit from any thoughts you all may have on a DIY home control system. My ultimate goal is to create a home control that will display all the menus/etc... as video. Then use a keyboard/mouse to interface. The system will control the T/V, DVD, VCR (I'm not old...I'm vintage), stereo, lights, shades and monitor outside temp (plus some other bells and whistles I'm sure). My only real confusion is the IR.
I always enjoy reading all your posts. Thanks
Phill
Comments
I have experimented with using IR to control a camera, and it is not that complicated. However, I was able to use equipment at work to decode the pulses from the IR controller. Our products use an IR remote control. I used an oscilliscope to determine the frequency. I found that IR receivers are not very sensitive to the frequency, and the IR control will work even if the transmitter is not sending exactly the right frequency. Standard frequencies are between 38 KHz and 60 KHz.
The IR codes are fairly simple. There are three main signals, which are the start bit, one bit and a zero bit. Each of these signals consists of a short burst at the IR frequency followed by a short period when the IR is off. The start bit, one bit and zero bit will have unique time periods for when they are on and off. Some remotes may use additional signals, such as a repeat signal that is used when holding a button down for a long time.
You could wire a processor to an IR detector and write a simple program to record on and off times. Once you know the on and off times you could then decode the codes sent by the IR detector for each button. I used an SX, but you can probably do this with a basic stamp.
Dave
Check out the posting "IR Repeater" cutomer applications, home application on the web sight.
http://www.parallax.com/html_pages/resources/custapps/app_irrepeater.asp
I used two BS2 stamps to work out the timing.
Search "IR Protocol" and or "IR Protocols"
Stephen.